Roll Clang 325667:327688

Clang r326867 turned on SafeStack when targeting Fuchsia by default.
Turn it off in our build config until all the tests pass.

Bug: 817298, 821951

Change-Id: Id2d9f911eb62fe6823365baeba55a4ccc0b484ce
Reviewed-on: https://chromium-review.googlesource.com/959003Reviewed-by: Nico Weber <thakis@chromium.org>
Commit-Queue: Hans Wennborg <hans@chromium.org>
Cr-Commit-Position: refs/heads/master@{#543745}

build/config/fuchsia/BUILD.gn

@@ -55,5 +55,9 @@ config("compiler") {
     "-Wl,--as-needed",
   ]
 
+  # TODO(crbug.com/821951): Clang enables SafeStack by default when targeting
+  # Fuchsia, but it breaks some tests, notably in V8.
+  cflags += [ "-fno-sanitize=safe-stack" ]
+
   libs = [ "zircon" ]
 }

tools/clang/scripts/update.py

@@ -27,7 +27,7 @@ import zipfile
 # Do NOT CHANGE this if you don't know what you're doing -- see
 # https://chromium.googlesource.com/chromium/src/+/master/docs/updating_clang.md
 # Reverting problematic clang rolls is safe, though.
-CLANG_REVISION = '325667'
+CLANG_REVISION = '327688'
 
 use_head_revision = bool(os.environ.get('LLVM_FORCE_HEAD_REVISION', '0')
                          in ('1', 'YES'))